- Email: [email protected]
How gender influences fibrosis regression in a chronic murine model of hepatic injury
POSTER PRESENTATIONS SAT-444 Genome wide methylation profile of liver from patients with severe hepatic fibrosis related to HCV infection L. Vasconcelos1,2, R.F. Carmo3, R. Emídio4, D. Aroucha4, S. Carvalho4, C. Chevillard5, P. Moura4, L.B. Pereira2,4, A. Dessein5. 1Research Center Aggeu Magalhães-FIOCRUZ-PE; 2Institute of Liver and Transplantation of Pernambuco, Recife; 3Federal University of São Francisco Valley, Petrolina; 4University of Pernambuco, Recife, Brazil; 5INSERM UMR906, Marseille, France E-mail: [email protected] Background and Aims: Hepatitis C virus (HCV) chronic infection causes liver fibrosis, which progress to cirrhosis and consequently liver transplantation in some patients. Recent studies have shown the importance of DNA methylation in the progression of liver fibrosis progression. Therefore, the exploration of DNA methylation in the early-stages of liver fibrosis may disclose triggering initial mechanisms of the hepatocarcinogenesis. Our aim was investigate the methylation profile of liver biopsies from patients infected with HCV. Methods: Liver needle biopsies samples from HCV-RNA positive patients obtained before treatment (n = 12), classified according METAVIR score, being 6 patients with early fibrosis (F0-F1) and 6 in advanced fibrosis (F3-F4). Liver DNA was extracted with Zimo research kit according manufactures instructions and Illumina HumanMethylation450 BeadChip arrays was used to identify regions of hypo- or hypermethylation that may influence hepatic fibrosis. Results: Regarding biochemical analysis, the serum levels of ALT, AST and the alpha-fetoprotein were higher in F3-F4 group ( p = 0.03, p = 0.01 and p = 0.04, respectively) characterizing active liver disease. Top methylation analysis of CpGs showed that cg26031046 at STAT2 gene (Signal transducer and activator of transcription 2) was hypermethylated in F3-F4 compared to F0-F1 liver samples ( p = 9.38 × 10E-7) with 32,8% median deference. Global analysis in the 5 kb distance of promoter regions from the genes revealed that the IFITM1 (Interferon induced transmembrane protein 1) gene was hypermethylated in F3F4 compared to F0-F1 liver samples ( p = 1,36E-05) showing 13.12% median difference. Pathways Enrichment analysis showed that cancer pathways (BSID: 83105) was associated to F3-F4 (PcBonf = 3.833E-4). Conclusions: Our results demonstrated that genes important to the viral response such as STAT2 and IFITM1 are epigenetically suppressed by methylation what could influence the development of fibrosis and consequently hepatocellular carcinoma in HCV infected patients. However more studies are necessary to confirm this hypothesis. SAT-445 Autophagy regulates endothelial dysfunction and hepatic fibrosis development M. Ruart1, L. Chavarria1, S. Guixe1, S.L. Friedman2, J. Bosch1,3, J.C. Garcia-Pagan1,3, V. Hernandez-Gea1,3. 1Hepatic Hemodynamic Laboratory, Liver Unit, Hospital Clínic, IDIBAPS, University of Barcelona, Barcelona, Spain; 2Division of Liver Diseases, Department of Medicine, Icahn School of Medicine at Mount Sinai, New York, United States; 3 CIBERehd, Madrid, Spain E-mail: [email protected] Background and Aims: Loss of liver sinusoidal endothelial cell (LSEC) phenotype, known as endothelial dysfunction (ED), is one of the first changes occurring in the liver after injury. ED precedes the onset of hepatic fibrosis, regulates hepatic stellate cell (HSC) activation and occurs spontaneously in vitro. The main regulatory pathways involved in ED are still not fully understood. Autophagy is a highly conserved mechanism essential for cellular homeostasis and the orchestration of an efficient cellular response to stress but its role in ED is not known. We aimed to investigate whether defects in LSEC autophagy contribute to the amplification of hepatic injury and fibrosis.
S652
Methods: Markers of autophagy (LC3, P62, flow) and endothelial phenotype (eNOS, iNOS, CD31, VEGFR2, endothelin-1) were evaluated in primary LSEC isolated from control rats, rats with fibrosis (CCl4 ip 4w) and with early cirrhosis (CCl4 ip 6w). Autophagy was induced (rapamycin 2 microM) and inhibited (3 MA 10 mM & cloroquine 20 microM) in LSEC from control rats and the impact on LSEC phenotype was evaluated. HSC were cultivated with conditioned medium from LSEC where autophagy was manipulated and fibrogenic markers (alpha-sma, Collagen-alphaI, pdgfr-beta) were assessed. Results: (1) Culture of LSEC initially induces autophagy levels that decline after 48 h, overlapping with the greatest change in LSEC phenotype (2) LSEC from fibrotic rats shows increased autophagy; however if injury persists, autophagy levels decrease coinciding with the onset of cirrhosis and suggesting inability of dysfunctional LSEC to further increase autophagy levels and restrict fibrosis progression. These results suggest that autophagy regulates ED in vitro and in vivo. (3) Autophagy-deficient LSEC exhibit accelerated ED, whereas autophagy overexpression in LSEC ameliorates the dysfunctional phenotype. (4) Conditioned media from endothelial cells with autophagy inhibition promotes HSC activation and fibrogenesis. In contrast, HSC cultivated with media from endothelial cells with autophagy upregulation maintain a more quiescent phenotype. These data suggest that the manipulation of endothelial autophagy impacts on ED and liver fibrosis. Conclusions: Autophagy regulates ED and contributes to development/perpetuation of fibrosis. Induction of endothelial autophagy attenuates fibrosis and could be an attractive target for antifibrotic therapy. SAT-446 How gender influences fibrosis regression in a chronic murine model of hepatic injury M. Crescenzi1, C. Frasson2, D. Gabbia3, S. De Martin3, M.T. Conconi3, G. Basso2, P. Burra1, F.P. Russo1. 1Gastroenterology Section, Department of Surgery, Oncology and Gastroenterology, University Hospital Padova; 2 Department of Woman and Child Health, University of Padova, Institute of Pediatric Research Città della Speranza -IRP; 3Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy E-mail: [email protected] Background and Aims: A dimorphic response to an acute liver damage was demonstrated by our laboratory in mice intraperitoneally (ip) injected with CCl4. With this research authors aim at unveiling gender-dependent mechanisms responsible for liver fibrosis regression in the setting of chronic liver damage, with a focus on macrophages emerging populations involved in liver damage resolution. Methods: Balb/cJ mice were ip injected with CCl4 twice a week (wk) and sacrificed at wk 2, 6, 12 and after 8 weeks from the cessation of the treatment (recovery). Fibrosis and stellate cells activation were evaluated, as well as Collagens I, III and IV, IL-6 and -10 and VEGF. Androgen Receptor+ and GAT6+ macrophage were evaluated by Flow Cytometry. Results: Significantly less fibrosis at wk 2 in treated females (mean ± ds females vs. males: 5.52 ± 1.01 vs. 8.4 ± 2.02 p = 0.021) was observed, compared to male mice. In the recovery the amount of fibrosis was higher in females with respect to males (mean ± ds females vs. males: 4.48 ± 1.39 vs. 2.46 ± 0.53 p = 0.032). Alpha-SMA+ areas were significantly higher in female than in male animals at wk 2 (mean ± ds females vs. males: 8.52 ± 0.7 vs. 5.47 ± 0.88 p = 0.009), and decreased over time (mean ± ds females at wk 2 vs. wk 12 and males wk 2 vs. wk 12: 8.52 ± 0.7 vs. 2.72 ± 0.24 p < 0.001 and 5.47 ± 0.88 vs, 1.58 ± 0.68 p = 0.004, respectively). No gender-related differences in CYP2E1 were observed at any time point. Collagens I, III and IV were found lower in females than in males at wk 2 with a reversed trend in the recovery group. IL-6 and IL-10 were found lower in females at wk
Journal of Hepatology 2017 vol. 66 | S543–S750
POSTER PRESENTATIONS 2 in respect to males. Male mice showed a significant increase of IL-6 and a significant decrease of IL-10 during the recovery period, differently from female mice. VEGF dramatically increased during the recovery period in both. Androgen Receptor+ macrophages, not physiologically found in females, were higher in females than in males both at wk 2 and in the recovery. On the contrary, GAT6+ macrophages were present in both in control mice and were higher in females at wk 2 in respect to males, showing a reversion in their abundance in the recovery group. Conclusions: These preliminary data suggest a premature activation of fibrogenic pathway in CCl4-treated female mice. A molecular mechanism, not CYP2E1-mediated, is supposed to be defective in females, considering the higher amount of fibrosis found in their livers after the recovery period. The female mice inflammatory status could explain, at least in part, their defects in fibrosis regression. SAT-447 Activated primary stellate cells show decreased aquaporin 3 expression in parallel with cellular senescence which is restored with PPAR-γ agonist establishing quiescence M. Tardelli1, F.V. Bruschi1, T.M. Stulnig2, M. Trauner1. 1Hans Popper Laboratory for Molecular Hepatology; 2Christian Doppler Laboratory for Cardio-Metabolic Immunotherapy, Medical university of Vienna, Vienna, Austria E-mail: [email protected] Background and Aims: Aquaporins are fundamental trans-membrane proteins which allow the movement of water and, in case of the aquaglyceroporins (AQPs) a subtype of aquaporins, glycerol, that is needed in quiescent hepatic stellate cells (HSC) for triglyceride formation and thus lipid storage. A previous study from our group showed the importance of AQP3 in glycerol uptake and lipid formation in LX2 cell line. In the present work we aimed at understanding the role of AQP3 in HSC activation in relation to a PPAR-γ agonist, Rosiglitazone. More specifically, we explored whether senescence and parallel activation could have a role in glycerol uptake, and therefore cell’s lipid content, and if this could be reversed with a PPAR-γ agonist. Methods: Primary HSC were isolated from liver unsuitable for transplantation, RT-PCR, western blot and flow cytometric staining were performed in LX2 and primary HSC. Immunofluorescence staining was carried out in paraffin embedded tissue from healthy and NASH donors. Proliferation assay and cell number were measured with a calorimetric assay Cell Titer Glo. Results: AQP3 was the only aquaglyceroporin represented in LX2 and primary HSC cells freshly isolated from human liver. Hereby, we showed how AQP3 protein and mRNA expression significantly decreases fivefold ( p < 0.01) in parallel with primary HSC activation in culture. Moreover, AQP3 surface expression was significantly reduced to one third on flow cytometric staining in parallel with features of cellular senescence ( p < 0.05). This focused our interest towards understanding the role of AQP3 in HSC activation, and whether it is present in NASH patients. Comparison of NASH patient’ liver with a healthy donor, revealed the co-localisation of AQP3 with alpha smooth muscle actin staining in vivo. Although AQP3 was less abundant in NASH liver, we discovered a co-localisation with a marker of HSCs activation. When activated human primary HSC were treated with the PPAR gamma agonist Rosiglitazone, AQP3 expression was significantly recovered ( p < 0.05) and in parallel they showed diminished proliferation ( p < 0.05) and a decreased amount of downstream targets of HSC activation ( p < 0.05) ( p < 0.01). Conclusions: In conclusion we demonstrated that AQP3 could be an interesting target within HSC activation which could be modulated with PPAR-γ in counteracting liver fibrosis.
SAT-448 Differential role of NLRP3 inflammasome during acute and chronic cholestatic liver injury M. Frissen1, L. Liao1, V. Bieghs1, K.M. Schneider1, A. Mohs1, E. Latz2, A. Wree1, C. Trautwein1. 1Medizinische Klinik III, Uniklinik RWTH Aachen, Aachen; 2Innate Immunity, University Clinic Bonn, Bonn, Germany E-mail: [email protected] Background and Aims: Cholestasis causes hepatic toxicity which leads to liver injury by cell death. Apoptotic and pyroptotic cell death is a consequence of caspase-8 and/or caspase-1 activation and is mediated by the NLRP3 inflammasome. NLRP3 activation triggers liver inflammation, fibrosis and hepatocyte pyroptosis in mice. Thus we here studied the role of NLRP3 inflammasome activation during cholestatic liver injury. Methods: To investigate the role of the NLRP3 inflammasome we performed bile duct ligation (BDL) in WT, NLRP3-/- and ASC-/mice. We were interested to study the role of NLRP3 during acute (48 hours) and chronic (28 days) injury after BDL. Inflammation, fibrosis and cell death were evaluated with qPCR, IHC, IF and western blot analysis. Results: Acute cholestatic liver injury in NLRP3-/- mice resulted in a significantly stronger increase in serum transaminases compared to WT mice. In addition hepatic inflammation, as shown by mRNA levels of TNF, IL-1b, MCP-1 and influx of Ly6G+CD11b+ cells by FACS analysis was observed. The increase in liver injury can be explained by a stronger necroptotic response in NLRP3-/- mice, as shown by an increase in mitochondrial ROS and RIPK1 and 3 expression. In contrast, during chronic cholestatic liver injury, lack of NLRP3 expression was protective as evidenced by reduced serum transaminases, less inflammation and reduced fibrosis. TUNEL and caspase-3 staining additionally showed decreased cell death in NLRP3-/- mice. Furthermore, caspase-3 staining showed clusters of increased cell death in WT mice 28d after BDL, associated with pyroptosis. This can be due to the inability of NLRP3-/- mice to activate caspase-1 and release IL-1b. Since RIP3-mediated necroptosis is increased in NLRP3-/- mice, expansion of progenitor/oval cells is triggered which could explain reduced liver injury. ASC-/- mice show an intermediate phenotype, after 2d BDL the serum transaminases and hepatic inflammation is elevated compared to WT mice but lower than the NLRP3-/-. In the chronic phase the ASC-/- mice are comparable to the NLRP3-/- mice, since they also lack inflammasome activation. Conclusions: During acute cholestatic liver injury lack of NLRP3 expression is associated with increased liver injury mediated by mitochondrial ROS and RIPK1 and 3 activation triggering increased necroptosis and a stronger inflammatory response. In contrast, in the chronic phase NLRP3-/- mice have less liver injury due to reduced pyroptotic cell death leading to less inflammation and fibrosis. SAT-449 Suppression of hepatic fibrosis by efficient Col1a1 silencing using shRNA inducible mouse models O. Molokanova1, K. Schönig2, S.-Y. Weng1, X. Wang1, M. Bros3, M. Diken4, S. Ohngemach5, M. Karsdal6, A. Nikolaev7, L. Eshkind5, D. Schuppan8. 1Institute of Translational Immunology, Research Center for Immunotherapy and the EPOS Consortium, University Medical Center, Johannes Gutenberg University, Mainz; 2Department of Molecular Biology, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim; 3Department of Dermatology; 4Institute for Translational Oncology (TrOn); 5Transgenic Facility Mainz, TARC, University Medical Center, Mainz, Germany; 6 Nordic Bioscience A/S, Herlev, Denmark; 7Institut of Molecular Medicine; 8Institute of Translational Immunology, Research Center for Immunotherapy and the EPOS consortium, University Medical Center, Mainz, Germany E-mail: [email protected]
Journal of Hepatology 2017 vol. 66 | S543–S750
S653
S652
Methods: Markers of autophagy (LC3, P62, flow) and endothelial phenotype (eNOS, iNOS, CD31, VEGFR2, endothelin-1) were evaluated in primary LSEC isolated from control rats, rats with fibrosis (CCl4 ip 4w) and with early cirrhosis (CCl4 ip 6w). Autophagy was induced (rapamycin 2 microM) and inhibited (3 MA 10 mM & cloroquine 20 microM) in LSEC from control rats and the impact on LSEC phenotype was evaluated. HSC were cultivated with conditioned medium from LSEC where autophagy was manipulated and fibrogenic markers (alpha-sma, Collagen-alphaI, pdgfr-beta) were assessed. Results: (1) Culture of LSEC initially induces autophagy levels that decline after 48 h, overlapping with the greatest change in LSEC phenotype (2) LSEC from fibrotic rats shows increased autophagy; however if injury persists, autophagy levels decrease coinciding with the onset of cirrhosis and suggesting inability of dysfunctional LSEC to further increase autophagy levels and restrict fibrosis progression. These results suggest that autophagy regulates ED in vitro and in vivo. (3) Autophagy-deficient LSEC exhibit accelerated ED, whereas autophagy overexpression in LSEC ameliorates the dysfunctional phenotype. (4) Conditioned media from endothelial cells with autophagy inhibition promotes HSC activation and fibrogenesis. In contrast, HSC cultivated with media from endothelial cells with autophagy upregulation maintain a more quiescent phenotype. These data suggest that the manipulation of endothelial autophagy impacts on ED and liver fibrosis. Conclusions: Autophagy regulates ED and contributes to development/perpetuation of fibrosis. Induction of endothelial autophagy attenuates fibrosis and could be an attractive target for antifibrotic therapy. SAT-446 How gender influences fibrosis regression in a chronic murine model of hepatic injury M. Crescenzi1, C. Frasson2, D. Gabbia3, S. De Martin3, M.T. Conconi3, G. Basso2, P. Burra1, F.P. Russo1. 1Gastroenterology Section, Department of Surgery, Oncology and Gastroenterology, University Hospital Padova; 2 Department of Woman and Child Health, University of Padova, Institute of Pediatric Research Città della Speranza -IRP; 3Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy E-mail: [email protected] Background and Aims: A dimorphic response to an acute liver damage was demonstrated by our laboratory in mice intraperitoneally (ip) injected with CCl4. With this research authors aim at unveiling gender-dependent mechanisms responsible for liver fibrosis regression in the setting of chronic liver damage, with a focus on macrophages emerging populations involved in liver damage resolution. Methods: Balb/cJ mice were ip injected with CCl4 twice a week (wk) and sacrificed at wk 2, 6, 12 and after 8 weeks from the cessation of the treatment (recovery). Fibrosis and stellate cells activation were evaluated, as well as Collagens I, III and IV, IL-6 and -10 and VEGF. Androgen Receptor+ and GAT6+ macrophage were evaluated by Flow Cytometry. Results: Significantly less fibrosis at wk 2 in treated females (mean ± ds females vs. males: 5.52 ± 1.01 vs. 8.4 ± 2.02 p = 0.021) was observed, compared to male mice. In the recovery the amount of fibrosis was higher in females with respect to males (mean ± ds females vs. males: 4.48 ± 1.39 vs. 2.46 ± 0.53 p = 0.032). Alpha-SMA+ areas were significantly higher in female than in male animals at wk 2 (mean ± ds females vs. males: 8.52 ± 0.7 vs. 5.47 ± 0.88 p = 0.009), and decreased over time (mean ± ds females at wk 2 vs. wk 12 and males wk 2 vs. wk 12: 8.52 ± 0.7 vs. 2.72 ± 0.24 p < 0.001 and 5.47 ± 0.88 vs, 1.58 ± 0.68 p = 0.004, respectively). No gender-related differences in CYP2E1 were observed at any time point. Collagens I, III and IV were found lower in females than in males at wk 2 with a reversed trend in the recovery group. IL-6 and IL-10 were found lower in females at wk
Journal of Hepatology 2017 vol. 66 | S543–S750
POSTER PRESENTATIONS 2 in respect to males. Male mice showed a significant increase of IL-6 and a significant decrease of IL-10 during the recovery period, differently from female mice. VEGF dramatically increased during the recovery period in both. Androgen Receptor+ macrophages, not physiologically found in females, were higher in females than in males both at wk 2 and in the recovery. On the contrary, GAT6+ macrophages were present in both in control mice and were higher in females at wk 2 in respect to males, showing a reversion in their abundance in the recovery group. Conclusions: These preliminary data suggest a premature activation of fibrogenic pathway in CCl4-treated female mice. A molecular mechanism, not CYP2E1-mediated, is supposed to be defective in females, considering the higher amount of fibrosis found in their livers after the recovery period. The female mice inflammatory status could explain, at least in part, their defects in fibrosis regression. SAT-447 Activated primary stellate cells show decreased aquaporin 3 expression in parallel with cellular senescence which is restored with PPAR-γ agonist establishing quiescence M. Tardelli1, F.V. Bruschi1, T.M. Stulnig2, M. Trauner1. 1Hans Popper Laboratory for Molecular Hepatology; 2Christian Doppler Laboratory for Cardio-Metabolic Immunotherapy, Medical university of Vienna, Vienna, Austria E-mail: [email protected] Background and Aims: Aquaporins are fundamental trans-membrane proteins which allow the movement of water and, in case of the aquaglyceroporins (AQPs) a subtype of aquaporins, glycerol, that is needed in quiescent hepatic stellate cells (HSC) for triglyceride formation and thus lipid storage. A previous study from our group showed the importance of AQP3 in glycerol uptake and lipid formation in LX2 cell line. In the present work we aimed at understanding the role of AQP3 in HSC activation in relation to a PPAR-γ agonist, Rosiglitazone. More specifically, we explored whether senescence and parallel activation could have a role in glycerol uptake, and therefore cell’s lipid content, and if this could be reversed with a PPAR-γ agonist. Methods: Primary HSC were isolated from liver unsuitable for transplantation, RT-PCR, western blot and flow cytometric staining were performed in LX2 and primary HSC. Immunofluorescence staining was carried out in paraffin embedded tissue from healthy and NASH donors. Proliferation assay and cell number were measured with a calorimetric assay Cell Titer Glo. Results: AQP3 was the only aquaglyceroporin represented in LX2 and primary HSC cells freshly isolated from human liver. Hereby, we showed how AQP3 protein and mRNA expression significantly decreases fivefold ( p < 0.01) in parallel with primary HSC activation in culture. Moreover, AQP3 surface expression was significantly reduced to one third on flow cytometric staining in parallel with features of cellular senescence ( p < 0.05). This focused our interest towards understanding the role of AQP3 in HSC activation, and whether it is present in NASH patients. Comparison of NASH patient’ liver with a healthy donor, revealed the co-localisation of AQP3 with alpha smooth muscle actin staining in vivo. Although AQP3 was less abundant in NASH liver, we discovered a co-localisation with a marker of HSCs activation. When activated human primary HSC were treated with the PPAR gamma agonist Rosiglitazone, AQP3 expression was significantly recovered ( p < 0.05) and in parallel they showed diminished proliferation ( p < 0.05) and a decreased amount of downstream targets of HSC activation ( p < 0.05) ( p < 0.01). Conclusions: In conclusion we demonstrated that AQP3 could be an interesting target within HSC activation which could be modulated with PPAR-γ in counteracting liver fibrosis.
SAT-448 Differential role of NLRP3 inflammasome during acute and chronic cholestatic liver injury M. Frissen1, L. Liao1, V. Bieghs1, K.M. Schneider1, A. Mohs1, E. Latz2, A. Wree1, C. Trautwein1. 1Medizinische Klinik III, Uniklinik RWTH Aachen, Aachen; 2Innate Immunity, University Clinic Bonn, Bonn, Germany E-mail: [email protected] Background and Aims: Cholestasis causes hepatic toxicity which leads to liver injury by cell death. Apoptotic and pyroptotic cell death is a consequence of caspase-8 and/or caspase-1 activation and is mediated by the NLRP3 inflammasome. NLRP3 activation triggers liver inflammation, fibrosis and hepatocyte pyroptosis in mice. Thus we here studied the role of NLRP3 inflammasome activation during cholestatic liver injury. Methods: To investigate the role of the NLRP3 inflammasome we performed bile duct ligation (BDL) in WT, NLRP3-/- and ASC-/mice. We were interested to study the role of NLRP3 during acute (48 hours) and chronic (28 days) injury after BDL. Inflammation, fibrosis and cell death were evaluated with qPCR, IHC, IF and western blot analysis. Results: Acute cholestatic liver injury in NLRP3-/- mice resulted in a significantly stronger increase in serum transaminases compared to WT mice. In addition hepatic inflammation, as shown by mRNA levels of TNF, IL-1b, MCP-1 and influx of Ly6G+CD11b+ cells by FACS analysis was observed. The increase in liver injury can be explained by a stronger necroptotic response in NLRP3-/- mice, as shown by an increase in mitochondrial ROS and RIPK1 and 3 expression. In contrast, during chronic cholestatic liver injury, lack of NLRP3 expression was protective as evidenced by reduced serum transaminases, less inflammation and reduced fibrosis. TUNEL and caspase-3 staining additionally showed decreased cell death in NLRP3-/- mice. Furthermore, caspase-3 staining showed clusters of increased cell death in WT mice 28d after BDL, associated with pyroptosis. This can be due to the inability of NLRP3-/- mice to activate caspase-1 and release IL-1b. Since RIP3-mediated necroptosis is increased in NLRP3-/- mice, expansion of progenitor/oval cells is triggered which could explain reduced liver injury. ASC-/- mice show an intermediate phenotype, after 2d BDL the serum transaminases and hepatic inflammation is elevated compared to WT mice but lower than the NLRP3-/-. In the chronic phase the ASC-/- mice are comparable to the NLRP3-/- mice, since they also lack inflammasome activation. Conclusions: During acute cholestatic liver injury lack of NLRP3 expression is associated with increased liver injury mediated by mitochondrial ROS and RIPK1 and 3 activation triggering increased necroptosis and a stronger inflammatory response. In contrast, in the chronic phase NLRP3-/- mice have less liver injury due to reduced pyroptotic cell death leading to less inflammation and fibrosis. SAT-449 Suppression of hepatic fibrosis by efficient Col1a1 silencing using shRNA inducible mouse models O. Molokanova1, K. Schönig2, S.-Y. Weng1, X. Wang1, M. Bros3, M. Diken4, S. Ohngemach5, M. Karsdal6, A. Nikolaev7, L. Eshkind5, D. Schuppan8. 1Institute of Translational Immunology, Research Center for Immunotherapy and the EPOS Consortium, University Medical Center, Johannes Gutenberg University, Mainz; 2Department of Molecular Biology, Central Institute of Mental Health, Medical Faculty Mannheim/Heidelberg University, Mannheim; 3Department of Dermatology; 4Institute for Translational Oncology (TrOn); 5Transgenic Facility Mainz, TARC, University Medical Center, Mainz, Germany; 6 Nordic Bioscience A/S, Herlev, Denmark; 7Institut of Molecular Medicine; 8Institute of Translational Immunology, Research Center for Immunotherapy and the EPOS consortium, University Medical Center, Mainz, Germany E-mail: [email protected]
Journal of Hepatology 2017 vol. 66 | S543–S750
S653